The invention relates to an electromagnetic actuating apparatus.
Apparatuses such as these have been known for a long time, for example as actuating apparatuses with electrical attraction magnets, and are used to fulfill a wide range of purposes. The fundamental principle is that an actuating element which is in the form of a piston and has an engagement area at the end for the intended actuating task is guided in a housing as an armature between a stationary core area and a mounting element, which acts as a yoke, and can be operated by means of an electromagnet which is provided approximately in the core area. The housing is normally designed to be permeable to magnetic flux, in order to close the magnetic circuit together with the mounting element, which acts as a yoke.
DE 102 40 774 A1 from the same applicant describes an electromagnetic actuating apparatus as claimed in the precharacterizing clause of claim 1. In the known actuating apparatus, the actuating element is formed integrally from a soft-magnetic material. The soft-magnetic material bundles the magnetic lines of force, thus increasing the magnetic field in the area of the actuating element as a result of which it is in turn possible to achieve faster switching times. However, the known actuating apparatus has the disadvantage that the mechanical loads, which unavoidably act on the engagement area, which is likewise formed from the soft-magnetic material, of the actuating element with little strength while carrying out the movement tasks lead to increased wear on the actuating element in the engagement area.
As prior art, DE 102 40 774 A1 from the same applicant also discloses an electromagnetic actuating apparatus which is not of the same generic type and has a resetting spring instead of permanent magnet means. In this apparatus, the actuating element is formed in three pieces. The three-piece embodiment is necessary in the known apparatus in order to form an opposing bearing for the resetting spring. The central subsection of the known actuating apparatus is used as an opposing bearing.
The invention is based on the object of making an electromagnetic actuating apparatus of this generic type more robust while still having short switching times.